diff options
Diffstat (limited to 'drivers/power/supply/wm97xx_battery.c')
| -rw-r--r-- | drivers/power/supply/wm97xx_battery.c | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/drivers/power/supply/wm97xx_battery.c b/drivers/power/supply/wm97xx_battery.c new file mode 100644 index 000000000..a0e1eaa25 --- /dev/null +++ b/drivers/power/supply/wm97xx_battery.c @@ -0,0 +1,276 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Battery measurement code for WM97xx + * + * based on tosa_battery.c + * + * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com> + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/power_supply.h> +#include <linux/wm97xx.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/gpio/consumer.h> +#include <linux/irq.h> +#include <linux/slab.h> + +static struct work_struct bat_work; +static struct gpio_desc *charge_gpiod; +static DEFINE_MUTEX(work_lock); +static int bat_status = POWER_SUPPLY_STATUS_UNKNOWN; +static enum power_supply_property *prop; + +static unsigned long wm97xx_read_bat(struct power_supply *bat_ps) +{ + struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps); + + return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent), + pdata->batt_aux) * pdata->batt_mult / + pdata->batt_div; +} + +static unsigned long wm97xx_read_temp(struct power_supply *bat_ps) +{ + struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps); + + return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent), + pdata->temp_aux) * pdata->temp_mult / + pdata->temp_div; +} + +static int wm97xx_bat_get_property(struct power_supply *bat_ps, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct wm97xx_batt_pdata *pdata = power_supply_get_drvdata(bat_ps); + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + val->intval = bat_status; + break; + case POWER_SUPPLY_PROP_TECHNOLOGY: + val->intval = pdata->batt_tech; + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + if (pdata->batt_aux >= 0) + val->intval = wm97xx_read_bat(bat_ps); + else + return -EINVAL; + break; + case POWER_SUPPLY_PROP_TEMP: + if (pdata->temp_aux >= 0) + val->intval = wm97xx_read_temp(bat_ps); + else + return -EINVAL; + break; + case POWER_SUPPLY_PROP_VOLTAGE_MAX: + if (pdata->max_voltage >= 0) + val->intval = pdata->max_voltage; + else + return -EINVAL; + break; + case POWER_SUPPLY_PROP_VOLTAGE_MIN: + if (pdata->min_voltage >= 0) + val->intval = pdata->min_voltage; + else + return -EINVAL; + break; + case POWER_SUPPLY_PROP_PRESENT: + val->intval = 1; + break; + default: + return -EINVAL; + } + return 0; +} + +static void wm97xx_bat_external_power_changed(struct power_supply *bat_ps) +{ + schedule_work(&bat_work); +} + +static void wm97xx_bat_update(struct power_supply *bat_ps) +{ + int old_status = bat_status; + + mutex_lock(&work_lock); + + bat_status = (charge_gpiod) ? + (gpiod_get_value(charge_gpiod) ? + POWER_SUPPLY_STATUS_DISCHARGING : + POWER_SUPPLY_STATUS_CHARGING) : + POWER_SUPPLY_STATUS_UNKNOWN; + + if (old_status != bat_status) { + pr_debug("%s: %i -> %i\n", bat_ps->desc->name, old_status, + bat_status); + power_supply_changed(bat_ps); + } + + mutex_unlock(&work_lock); +} + +static struct power_supply *bat_psy; +static struct power_supply_desc bat_psy_desc = { + .type = POWER_SUPPLY_TYPE_BATTERY, + .get_property = wm97xx_bat_get_property, + .external_power_changed = wm97xx_bat_external_power_changed, + .use_for_apm = 1, +}; + +static void wm97xx_bat_work(struct work_struct *work) +{ + wm97xx_bat_update(bat_psy); +} + +static irqreturn_t wm97xx_chrg_irq(int irq, void *data) +{ + schedule_work(&bat_work); + return IRQ_HANDLED; +} + +#ifdef CONFIG_PM +static int wm97xx_bat_suspend(struct device *dev) +{ + flush_work(&bat_work); + return 0; +} + +static int wm97xx_bat_resume(struct device *dev) +{ + schedule_work(&bat_work); + return 0; +} + +static const struct dev_pm_ops wm97xx_bat_pm_ops = { + .suspend = wm97xx_bat_suspend, + .resume = wm97xx_bat_resume, +}; +#endif + +static int wm97xx_bat_probe(struct platform_device *dev) +{ + int ret = 0; + int props = 1; /* POWER_SUPPLY_PROP_PRESENT */ + int i = 0; + struct wm97xx_batt_pdata *pdata = dev->dev.platform_data; + struct power_supply_config cfg = {}; + + if (!pdata) { + dev_err(&dev->dev, "No platform data supplied\n"); + return -EINVAL; + } + + cfg.drv_data = pdata; + + if (dev->id != -1) + return -EINVAL; + + charge_gpiod = devm_gpiod_get_optional(&dev->dev, NULL, GPIOD_IN); + if (IS_ERR(charge_gpiod)) + return dev_err_probe(&dev->dev, + PTR_ERR(charge_gpiod), + "failed to get charge GPIO\n"); + if (charge_gpiod) { + gpiod_set_consumer_name(charge_gpiod, "BATT CHRG"); + ret = request_irq(gpiod_to_irq(charge_gpiod), + wm97xx_chrg_irq, 0, + "AC Detect", dev); + if (ret) + return dev_err_probe(&dev->dev, ret, + "failed to request GPIO irq\n"); + props++; /* POWER_SUPPLY_PROP_STATUS */ + } + + if (pdata->batt_tech >= 0) + props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */ + if (pdata->temp_aux >= 0) + props++; /* POWER_SUPPLY_PROP_TEMP */ + if (pdata->batt_aux >= 0) + props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */ + if (pdata->max_voltage >= 0) + props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */ + if (pdata->min_voltage >= 0) + props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */ + + prop = kcalloc(props, sizeof(*prop), GFP_KERNEL); + if (!prop) { + ret = -ENOMEM; + goto err3; + } + + prop[i++] = POWER_SUPPLY_PROP_PRESENT; + if (charge_gpiod) + prop[i++] = POWER_SUPPLY_PROP_STATUS; + if (pdata->batt_tech >= 0) + prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY; + if (pdata->temp_aux >= 0) + prop[i++] = POWER_SUPPLY_PROP_TEMP; + if (pdata->batt_aux >= 0) + prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW; + if (pdata->max_voltage >= 0) + prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX; + if (pdata->min_voltage >= 0) + prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN; + + INIT_WORK(&bat_work, wm97xx_bat_work); + + if (!pdata->batt_name) { + dev_info(&dev->dev, "Please consider setting proper battery " + "name in platform definition file, falling " + "back to name \"wm97xx-batt\"\n"); + bat_psy_desc.name = "wm97xx-batt"; + } else + bat_psy_desc.name = pdata->batt_name; + + bat_psy_desc.properties = prop; + bat_psy_desc.num_properties = props; + + bat_psy = power_supply_register(&dev->dev, &bat_psy_desc, &cfg); + if (!IS_ERR(bat_psy)) { + schedule_work(&bat_work); + } else { + ret = PTR_ERR(bat_psy); + goto err4; + } + + return 0; +err4: + kfree(prop); +err3: + if (charge_gpiod) + free_irq(gpiod_to_irq(charge_gpiod), dev); + return ret; +} + +static int wm97xx_bat_remove(struct platform_device *dev) +{ + if (charge_gpiod) + free_irq(gpiod_to_irq(charge_gpiod), dev); + cancel_work_sync(&bat_work); + power_supply_unregister(bat_psy); + kfree(prop); + return 0; +} + +static struct platform_driver wm97xx_bat_driver = { + .driver = { + .name = "wm97xx-battery", +#ifdef CONFIG_PM + .pm = &wm97xx_bat_pm_ops, +#endif + }, + .probe = wm97xx_bat_probe, + .remove = wm97xx_bat_remove, +}; + +module_platform_driver(wm97xx_bat_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>"); +MODULE_DESCRIPTION("WM97xx battery driver"); |